Portable drill



Feb. 1, 1944. H. w. THORNBURG 2,340,351

PORTABLE DRILL Filed Nov. 9. 1940 2 Sh ets-Sheet 1 a a} 52 n 37 47 55 35:E I -/2 46 I h II I 22 i I 4s 24 s INVENTO BY QQMTW ATTORNEYS- -'Feb.1, 1944. H. w. THORNBU-RG 1 2,340,351 l PORTABLE DRILL I Filed Nov.9,1940 2 Sheets-Sheet 2 BY M PW ATTORNEYS.

Patented Feb. 1, 1944 PORTABLE DRILL Herbert W. Thornburg, SouthMilwaukee, Wis.,

assignor to Bucyrus-Erle Company, South Milwaukee, Wis., a corporationof Delaware Application November 9, 1940, Serial No. 364,993

13 Claims.

My invention relates to new and useful improvements in portable drills.

Heretofore the derrick masts of such drills, the telescopic type of mastin particular, have been supported by detachable braces. In raisin themast to operative position, or in dismantling it, much time and laborhave been required to attach (or detach) the braces. Furthermoredetachable braces are apt to become mislaid and must be packed orunpacked.

Accordingly it is a principal object of my invention to provide the mastof a drill with a new type of brace construction whereby the hoisting ofthe mast with its supporting braces can be commenced immediately andaccomplished speedily without attachment of any separate members; andwhereby, as the mast is lowered into carrying position, the braces fallsemi-automatically as a unit into collapsed transport position, withoutdetachment.

A further principal object is to provide an automatic catch for thetelescoping mast, which will permit its extension in erect position, andwill prevent its extension in all other positions.

In general a drill, such for example as is used for oil-well drilling,hag-three principal operating tackles with different functions, bestdescribed in connection withtheir respective sheaves at the top of themast. A single center crown drilling sheave at thetop of the mast is forthe tool-hoist and drilling line. Casing sheaves above the crowndrilling sheave arefor the casing line which handles the casing of thedrilled hole. A sand sheave, usually below the crown drilling sheave, isused for the bailer line. One feature of my invention relates to thecasing tackle and supports thereof.

Normally there are only two-sheaves at the top of'the mast for thecasing line, which is reeved two-line to a single-sheave casing block.But to handle heavy casings a four-part or sixpart reeving, with one ortwo upper auxiliary sheaves respectively, is necessary.

Heretofore there have been two principal methods of supporting theseauxiliary sheaves. In the first of these former methods, shear poles,independent of the derrick mast (sometimes even of the whole drill), andheld in position by guy lines or other means, have been employed. Theseshear poles are expensive, clumsy and hazardone, although they have animportant advantage, when built to stand astride the derrick mast, in

. that they permit the casing lines to b centered with respect to thedrilling line, without interfering therewith. In the second of theseformer methods, the auxiliary casing sheaves have been mounted directlyon the derrick mast below the drilling line sheave by means of a bracket(or ometimes a chain) attached to the mast. A serious objection to thismethod of mounting is that. if the horizontal bracket is long enough toachieve centering of the casing line over the casing, there is eccentricloading on the derrick mast. Shortening the bracket throws the casingline out of line, which renders erection of the casing, threading it inparticular, very diflicult. A further trouble with th second (i. e.,bracket) method of suspension is that the auxiliary sheaves, beingmounted below the drilling line sheave, will interfere with the drillingline if the auxiliary casing sheaves are so mounted that the casinglines are centered over the casing in line with the drilling line.

Accordingly a further principal object of my invention isto provid amethod of mounting the auxiliary casing sheaves which will achieve theadvantageous features of each of the above mentioned methods withouttheir accompanying defects, that is, to achieve centering of the cas insline, to prevent or reduce to a minimum eccentric loading on the derrickmast, and to mount the casing sheaves clear of the drilling and otheroperating lines.

In addition to my principal objects, above stated, I have worked out anumber of novel and useful details, which will b readily evident as thedescription progresses.

My invention consists in the novel parts and in the combination andarrangement thereof, which are defined in the appended claims, and ofwhich one embodiment is exemplified in the accompanying drawings, whichare hereinafter particularly described and explained.

Throughout the description th same reference number is applied to thesame member or to similar members.

Figure 1 is a side elevation of my drill with its mast in uprightoperative position, the dotted lines indicating certain braces partiallydismantled and in position preparatory to telescoping the derrick.

Figure 2 is a side elevation of my drill with its mast in its uprightposition, but partially telescoped, and with one more bracedisassembled.

Figure 3 is a side elevation of my drill with its mast completelytelescoped, and partially swung toward horizontal.

Figure 4 is a detail diagram showing the arrangement of the braces incollapsed position.

Figure 5 is a detail showing hook and bar, to lock the two portions ofmy mast together.

Figure 6 is a detail side elevation of the upper portion of the derrickmast showing the apparatus for handling casing, including strut,sheaves.

and block and tackle, taken along the line 6-45 in Figure 7.

Figure 7 is a detail front elevation of the same mast and easingequipment shown in Figure 6, taken along the line 1-1 in Figure 6.

Figure 8 is a diagram of the casing line reeving.

-. sign, the details of which do not constitute any part of myinvention. In accordancewith the usual design, the foot portion l2 ofthe mast is pivotally mounted at the rear top corner of the frame ll, topermit tilting to a horizontal carrying position on top of the frame,from the substantially vertical extended operative (i. e., erected)position. The mast is, in its preferred form,

made up of two rigid telescoping sections, namely the foot i2 and theextensible portion 13.

My mast is braced in its vertical position by my improved constructionof collapsible folding braces, of which the construction shown anddescribed herein is merely an illustrative form.

It is a feature of my construction that certain of my braces form acontinuous linked chain from a point on my base to a point adjacent theouter end of my mast, and remain permanently attached to these points;while certain other braces, pivotally attached to this chain. at alltimes, are detachably pivoted to my base and my mast at points which arereadily accessible, at least at the times when it is necessary to attachor detach them successively.

All of these braces will now be described.

The chain consists preferably of 'three link braces, l5, l6 and I1,numbered successively from the bottom up.

Lower linlebrace i5 is pivotally supported by base II, and is pivotallyattached to lower link plate l8. Lower link brace I5 is preferablypivotally attached directly to the base ll adjacent the pivot at thefoot l2 of the mast, rather than to the foot l2. My preference for suchdirect support is that it enables the bottom of this link brace i5 to bemore widely spread than would be possible if the lower end of link bracel5 were attached to the foot l2.

Middle link brace I6 is pivotally attached to lower link plate It and toupper link plate i9.

Upper link brace I1 is pivotally attached to upper link plate I! and tothe extensible portion l3 of my mast, preferably to the top thereof.

Lower diagonal brace 20 is pivotally attached to the chain, preferablyat lower link plate It, and is detachably pivotally supported by thebase II, at widely spaced points remote the-mast.

Upper diagonal brace 2| is pivotally attached to the chain, preferablyat upper link plate l9, and is detachably pivotally supported by themast, preferably adjacent the upper end of the foot member l2 thereof.

Lower substantially horizontal brace 22 is pivotally attached to thechain, preferably at lower link plate l8, and is detachably pivotallysupported by the mast, preferably adjacent the upper end of the foot l2thereof.

Upper substantially horizontal brace 23 is pivotally attached to thechain, preferably at upper link plate l9, and is detachably pivotallysupported by the mast, preferably at some mid point of the extensibleportion l3 thereof;

When, in the claims, I describe any element as pivotally supported by asecond element, I intend to cover generically supporting the firstelement either directly or indirectly by the second element.

The detachable pivotal attachments, above referred to, can be of anyconvenient sort, such as bolts or pins, their exact nature diagonalbrace 2|, for a purpose which will be made evident hereinafter.

Although I have stated earlier herein that the details of my telescopingmast do not constitute a part of my invention, nevertheless it isessential to the eflicient operation thereof that the means forextending the extensible portion I! of my mast be such as, whenfirstapplied, to tilt my mast from a horizontal position to asubstantially vertical (preferably just past vertical) position, andthen-holding it thus-to extend the extensible portion. Such means is thetackle shown and described in the copending application of George R.Watson, filed September 16, 1937, Serial No. 164,109, now Patent No.2,251,- 309, dated August 5, 1941, for Improvements in multi-usewinch-tool for well drills, assigned to my assignee.

But, in connection therewith, I now employ a book 25, pivoted on thebottom end of the extensible portion l3 of my mast, and engageable witha bar 26 on the bottom end of the foot portion l2 of my mast. The bookis so balanced that when my mast is in its erected position (preferablya little past vertical, as already stated), the hook 25 willautomatically hang clear of the bar 26 by gravity, but willautomatically engage therewith as my mast tilts back through verticaltoward horizontal.

To lower my mast, from its erected position as shown in Figure 1, theoperator-first mounts to the top of the foot portion l2, as by a ladder(not shown) built thereon, and detaches the adjacent ends of upperdiagonal brace 2| and lower horizontal brace 22, which then hang free,interconnected by tension member 24, as shown dotted in Figure 1.

The lower end of the lower diagonal brace 20 is then detached from thebase, and is swung toward the mast, and is lashed to lower link brace iiin any convenient manner, as by lashings 21. This step could beperformed prior to the firstmentioned step, if desired.

The extensible portion I 3 of my mast is then lowered until the point ofattachment of upper horizontal brace 23 is within easy reach of theoperator, still perched near the top of the foot portion l2, as shown inFigure 2. He then unhitches this attachment. The lower end of thesupporting strut 38 for the auxiliary casing line tached at this time.

The extensible portion l3 of the mast can I then be completely lowered.

With further paying out of the raising tackle, the weight of the braces,having a long torquearm by virtue of being held 03 from the mast bylower link brace l5, tips the mast over as shown in Figure 3.

As this tipping starts, hook 25-automatically swings by gravity intoengagement with bar 26. This is very important, as otherwise, in theposition shown in Figure 3, the tension in the raising tacklewould causethe extensible portion l3 of the mast to shoot out.

, As the mast, telescoped' and hooked together, swings down towardhorizontal, the upper diagonal brace 2| may have to be guided away fromthe mast by hand, and upper horizontal brace 23 may have to be guidedtoward the mast by hand,

so that the braces will all lie in the position shown in Figure 4; butthe tension member 24 should guide braces 2| and 22 into their properpositions.

Raising. is an even more simple operation.

Drawing in on the raising tackle tilts the mast,

telescoped and hooked together to its past vertical position, whereuponhook 25 automatically falls free of bar 26.

Further pull on the tackle extends the extensible portion I3 to theposition of Figure 2, whereupon the operator can attach upper horizontalbrace 23, as there shown.

Still further pull on the tackle extends the extensible portion l3 tothe position of Figure 1,

whereupon braces 2|], 2| and 22, and supporting strut 38, can beattached as there shown, thus completing erection.

Referring now to Figures 6 to 8, we see that the casing tackle equipmentis arranged and mounted on the extensible portion I3 of my mast asfollows. At the top of the mast we have casing line sheaves 3i and 32,and "crown drilling line sheave 33 thereunder. The casing line sheaves3| and 32 are of radius sufficient to locate the casing line 34 over thecasing, parallel with the drilling line 35, and at a working distancefrom the mast. Above the drilling line sheave 33, and preferably aboveor level with the casing line sheaves 3| and 32, and lying in verticalplanes perpendicular to the planes of the casing line sheaves 3i and 32near the forward edges there- .of (to maintain the casing line parallelwith the drilling line) are the auxiliary casing line sheave or sheaves36, 31, which are mounted on the supporting strut 38. The base of thisstrut is bolted, or otherwise secured, preferably detachably, to thelower portion of the upper extensible part E3 of the mast at a bracedpoint 39 thereof, preferably at or near the upper horizontal brace 23,which thus takes the horizontal component of the load on said strut. Thetop of the strut is rigidly attached at the top of the mast by suitablemeans, such as a brace, or, as in my embodiment, a pin connection t2between two overlapping ears 4!] and 4! extending from the mast andstrut respectively. It is to be noted that, inasmuch as this attachmentis adjacent to the point of attachment of upper link brace I! to themast, this brace takes a part of the load on said strut. The describedlocation of the points of attachment of the strut t0 the mast isimportant, as relieving the mast of bending strains, which the strutwould otherwise impose.

Referring now to Figure 8, let us examine the casing line reeving'. Thisfigure shows a six-line reeving, but it should be understood that myinvention is not limited thereto. Casing line 34 passes from aconventional powered calf reel (no part of my invention) on the maindrill frame it and diagrammatically indicated at 43 only, underdeflecting sheave 44 on the drill frame, up over the right-hand casingsheave 31 at the top of the mast, twice down through the forward sheaves41, 46 of the casing block 50 (shown with a conventional hook 5|), twiceback up over the auxiliary casing line sheaves 31, 36, thendown throughthe rear sheave of the casing block 50 and up over the left-hand casingsheave 32 on the top of the mast, and thence to an anchorage 48 on thedrill frame. The purpose of passing the casing line over the dead casingsheave 32 to a dead end on the drill frame II is to achieve a balancedloading on the derrick mast, but such a method of reeving is notnecessary, although it is preferable. Any other,

suitable reeving utilizing my strut-supported auxiliary casing sheavesmay be adopted.

Referring now again to Figures 6 and 7, let us examine the function ofthe various parts in the light of my objects. First we see that theauxiliary casing line sheaves 36 and 31 are so ounted relative to thedrilling line sheave 33 that the casing line which passes through themfallsto the casing approximately centered and parallel to the drillingline 35. Secondly we see that, in spite of this alignment and centering,eccentric loading on the derrick mast is minis mized and directlydisposed of through the strut 38 to the upper horizontal brace 23 andthe vertical mast at 39, and through the connected ears 40 and to theupper link brace H at the top of the mast, as already stated. Thirdly wesee that the auxiliary casing line sheaves 38, 31 do not interfere withthe drilling line crown sheave 33, in spite of the above mentionedalignment, because they are placed above said crown sheave; and that thestrut 38 itself does not interfere with the crown sheave 33 or thedrilling line 35 which passes through the sheave, because of the slot oropening 45 in the strut 38, through which the crown sheave 33 protrudesand the drilling line-35 passes.

Having now described and illustrated one form of my invention, I wish itto be understood that my invention is not to be limited to the specificform or arrangement of parts herein described and shown, except asspecifically covered by my claims.

I claim:

1. In a drill, the combination of: a base; a foot portion of a mast,pivoted on the base for tilting from a substantially horizontal positionto a substantially vertical position; an extensible portion of the mast,extensible upwardly longitudinally along the foot portion; a jointedchain of three link braces, extending from a pivotal support on the baseadjacent the pivot of the foot portion of the mast to a pivotalconnection with the mast adjacent its upper end; a lower diagonal brace,pivotally attached to the chain adjacent the chain's lower joint, anddetachably pivotally supported by the base distant from the pivot of thefoot portion of the mast; a lower substantially horizontal brace,pivotally attached to the chain adjacent the chains lower joint, anddetachably pivotally supported by the foot portion of the mast adjacentits upper end; an upper diagonal brace, pivotally attached to the chainadjacent the chains upper joint, and

detachably pivotally supported by the foot portion of the mast adjacentits upper end; and an upper substantially horizontal brace, pivotallyattached to the chain adjacent the chains upper joint, and detachablypivoted on the extensible portion of the mast intermediate its ends.

2. A drill, according to claim 1, characterized further by having atension element connecting the lower horizontal brace and the upperdiagonal brace adjacent their detachable ends.

3. In a. drill, the combination of: a base, a foot portion of a mast,pivoted on the base for tilting from a substantially horizontal positionto a substantially vertical position; an extensible portion of the mast,extensible upwardly longitudinally along the foot portion; a jointedchain of link braces, extending from a pivotal connection with the baseto a pivotal connection with the mast adjacent its upper end; a lowerdiagonal brace, pivotally attached to the chain adjacent the chain'slower joint, and detachably pivotally supported by the base; a lowersubstantially horizontal brace, pivotally attached to the chain adjacentthe chain's lower joint, and detachably pivotally supported by the mastadjacent the upper end of the foot portion thereof; an upper diagonalbrace, pivotally attached to the chain adjacent an upper joint of thechain, and detachably pivotally supported by the mast;

and an upper substantially horizontal brace.

pivotally attached to the chain adjacent an upper joint of the chain,and detachably pivoted jointed chain of link braces, extending from, a

pivotal connection with the base to a pivotal connection with the mast;diagonal braces, each pivotally attached to the chainadjacent one of thechain's joints, at least one thereof being detachably pivotally attachedto the mast; and substantially horizontal braces, each pivotallyattached to the chain adjacent one of its joints, and each pivotallyattached to the mast, at least one thereof being detachably so attached.

6. In a drill, the combination of a base; a foot portion of a mast,pivoted on the base for tilting from a substantially horizontal positionto a substantially vertical position; an extensible portion of the mast,extensible upwardly longitudinally along the foot portion of the mast; ajointed chain of link braces, extending from a pivotal connection withthe base to a pivotal connection with the mast; diagonal braces, eachpivotally attached to the chain, at least'one thereof being detachablypivotally attached to the mast; and substantially horizontal braces,each pivotally attached to the chain, and each pivotally attached to themast. at least one thereof being detachably so attached.

.7. A drill, according to claim 1, in which the mast is adapted tohorizontal position to a substantially vertical position, and having:automatic catch means, consisting of two engageable members, one beingon each portion of the mast, whereby the two portions of the mast areautomatically locked against extension in all positions except thesubstantially vertical position,-in which position they areautomatically unlocked.

8. A drill, according to claim 3, in which the mast is adapted to pivotfrom a substantially horizontal position to a substantially verticalposition, and haw'ng: automatic catch means, consisting of twoengageable members, one being on each portion of the mast, whereby thetwo. portions of the mast are automatically locked against extension inall positions except the substantially vertical position, inwhichposition they are automatically unlocked.

9. In a drill, the combination of a base, a foot portion of a mast,pivoted on the base for tilting irom a substantially horizontal positionto a substantially vertical position; an extensible portion of the mast,extensible upwardly longitudinally along the foot portion of the mast;

pivot from a substantially at a pointbelow the top of the callyunlocked.

10. A drill, according to claim 9, wherein the catch means consists ofan engagement carried by the foot portion of the mast; and a hookhanging pivotally from the extens ible portion of the mast, and biasedto engage the engagement in all positions of the mast except itssubstantially vertical position, and to swing clear of the engagementwhenever the mast is in its substantially vertical position.

11. In a drill, which includes: a base; a sub-, stantially vertical mastthereon; slant bracing means, supporting the mast by extending from thebase to the mast at a point adjacent the top of the mast; asubstantially horizontal brace,

extending from said bracing means at a point below the top of the mast;and a drilling sheave, supported by the mast adjacent its top: incombination therewith, the following: two parallel casing hoist sheavesadjacent the top of the mast, one being on each side of the mast; aninclined'strut, supported by the mast, adjacent the point of attachmentof the horizontal brace; a support for the upper end of the strut,supported by the mast adjacent the point of atto the mast tachment oithe slant brace; and at least one pivoted on the strut above the leveloi sheave, the drilling sheave-adjacent the upper end of the strut, andlying in a plane perpendicular to the plane of the-casing hoist sheaves.

12. In a drill, which includes:

a base; a substantially vertical mast thereon;

slant bracing means, supporting the mast by extending from' the base tothe mast at a point adjacent the top of the mast; asubstantiallyhorizontal brace, extending from said bracing means to the mast mast;and a drilling sheave, supported by the mast adjacent its top: incombination therewith, the following: two parallel casing hoist sheavesadjacent the top of the mast, one being on each side of the mast;aninclined strut, supported by the mast, adjacent the point ofattachment of the horizontal brace; a support for the upper end of thestrut, supported by the mast adjacent the point of attachment of theslant brace; and at least one sheave, pivoted on the strut adjacent itsupper end, and lying in a plane perpendicular to the plane of the casinghoist sheaves.

13. In a drill, which includes: a base; a sub stantially vertical massthereon; slant bracing means, supporting the mast by extending from thebase to the mast at a point adjacent the top of the mast; and a drillingsheave, supported by the mast adjacent its top, in combinationtherewith, the following: substantially coaxial laterally spaced casinghoist sheaves supported by the mast adjacent its top; an inclined strut,supported by the mast at a point substantially below the top of themast; a support for the upper end of the strut, Supported by the mastadjacent the point of attachment of the slant brace; at least one casinghoist sheave, pivoted on the strut adjacent its upper end, and lying ina plane perpendicular to the plane of the easing hoist sheaves; and acasing hoist line trained over the casing hoist sheaves.

HERBERT W. 'I'HORNBURG.

